Genes
by tarballGZ
Summary: In the far future, the Okumura twins investigate an abandoned genetics lab of dubious legality. No one has been able to survive down there long enough to discover what sort of demon killed the researchers. When they come face to face with it and realize how frightening familiar it looks, can Rin take the painful route, or will he try to find another way to deal with him?


**Disclaimer**: I don't own Blue Exorcist.

* * *

"We were told to kill whatever we found, Nii-san." Yukio said curtly.

"Yeah…but…" Rin shook, staring horrified at the unkempt preteen huddling in front of them, stark naked aside from a thick black collar.

"It has killed people." Yukio reminded him.

"It?!" Rin exclaimed, wincing, turning toward his brother.

Startled by the loud noise, 'it' let out a guttural scream, leaping at Rin with its claws extended. Rin knocked the demon aside with tremendous force, slamming it into the wall of the darkened laboratory. It fell to the floor, leaving broken shelves and glass in its wake. Rin continued to eye the boy, and the demon returned his gaze with fear. Growling, he ran into the corridor, stepping on broken glass along the way and trailing small drops of blood.

"Crap. We need to follow it." Yukio dug his cell phone out and dialed the reinforcement team waiting on the surface.

"The situation is much worse than the Intelligence Division thought. Prepare as many vats of the most potent holy water you can find! Treat this enemy as if he were a demon king!"

Yukio put the phone down.

"We need to go, Nii-san. We can't let it reach the surface."

"Stop calling him 'it!'" Rin shot back, looking away an instant later. "Who would do something like this…?" He mouthed.

"Clone the son of Satan? I can think of very few people who wouldn't, if they had the resources and material."

"I'm not going to kill him. I don't care what our orders were."

"Do you have a way to get him under control, then?! He might look like a younger version of you, but he's feral! He's extremely dangerous!"

"He's _frightened_!"

Rin ran out of the room before Yukio could answer him, and Yukio sighed. Remaining in the room, he looked around, noticing an assortment of papers pinned to the wall, describing the clone's growth. He wasn't their first attempt at recreating Rin, but the previous ones failed to develop, yielded sick infants, or the children remained human and were disposed of by toddlerhood. It made Yukio sick. This boy, #0014, was already twelve years old…how many years had this project gone unnoticed by the Order of the True Cross? Yukio took all of the papers off of the board and skimmed through them. It seemed the boy was kept unconscious for the first decade of his life, to keep the flames from sending him out of control… No wonder he acted demonic, functionally he wasn't much better than a two year old. It was very unlikely he could be reasoned with.

Rin saw the trail of blood in front of him, but he didn't need to follow it to know where the boy had run off to. Rin's demon sensing abilities were screaming the boy's location at him. Down the hallway, hang a right, and there he was, scratching the steel wall and melting it with his flames. He looked back at Rin and screamed again, his ankle-long hair swishing behind him.

"Ain't gonna hurt ya. But you've gotta calm down." Rin said softly.

The boy screeched and threw flames at Rin, who jumped a dozen feet in the air to avoid them, clinging to the high ceiling. The boy backed up against the wall and Rin landed directly in front of him.

"Are you gonna be good?" he asked.

"Beeguud beeguuud… Beeguud! No! No! No! Dabret! Nnnndug." the clone muttered in a slurred voice, trying to push Rin away. Rin hugged him, and they both blew up in flames. Rin winced as they charred his skin, but did nothing to retaliate against him.

"Can you understand me?" Rin asked.

The boy stopped using the fire, confused, realizing the futility of attacking the older man.

"I doubt he can, Nii-san. He was only taught basic commands, and otherwise has developed his own words to communicate with the researchers growing him." Yukio said from behind him, holding a stack of papers in his hands. "He never had the opportunity to develop language capacity beyond that, after all. 'Dabret' seems to mean 'I am unhappy.' Nnnndug means he's hungry. The translations are written here." Yukio motioned with the papers.

The clone shuddered at the sound of rustling, igniting the sheets in blue fire which quickly spread up Yukio's arm. Yukio shook the fire off, glaring at the boy as the skin on his forearm quickly regenerated. His coat wasn't so lucky, hanging in tatters at the elbow.

The boy wasn't making eye contact, but Rin frowned at his twin brother. "Well of course he'd be unhappy and hungry. He's been stuck down here alone for almost two weeks."

Rin's young clone continued to mutter and shake in his progenitor's arms.

Rin turned back to the boy, continuing to speak to his brother. "Can you get some food for him? Maybe he'll calm down."

"He hasn't been fed because he incinerated everyone who approached him! And everyone who worked here! Nii-san…it's unlike you to forgive a demon after they've killed someone. It shouldn't matter what…or who…they look like." Yukio said coldly, before turning and walking down the hallway.

Rin nodded slowly and gripped the boy tighter. The boy soon stopped struggling against him, but continued to whimper.

Several minutes later, Yukio returned with canned food marked "#0014 Meat Formula (Reward)" and handed it to Rin, who opened it for the boy. As soon as he smelled it, the boy grabbed it and scarfed it down happily.

Rin smiled. "I've decided, Yukio."

Yukio looked at him nervously. "Decided what?"

"I'm gonna adopt him."

"Are you insane?!"

"The Vatican's going to try to kill him, just because of his power. He's the same as us."

"They want to kill him because he has killed humans. We were raised human, and functioned within human society. This is an animal!"

"If he's my clone, he can be taught he was wrong! He's got a human brain, hasn't he? The Vatican's never thought of us as human anyways… We're their attack dogs…no different from this kid here. Doesn't it bother you to see other people treated to like that?!"

"I warned you about those matters back when you decided to be an exorcist."

"That's me. And you were still human back then."

Yukio sighed. It did bother him, but he wasn't going to let those feelings affect his decisions. "We have had many years to adjust to their treatment of us…And he'll live the same life as us."

"Yukio…" Rin hesitated. "I want a child. You have no idea how badly I wanted to raise a child…And yet considering what I am…"

"The Vatican has forbidden us from reproducing, what do you think they'll do to him?!"

"They can be reasoned with now. I did what they wanted for other reasons. There's the pregnancy to worry about, I don't think a human could survive it…" Rin winced, on the verge of crying. "They said they'd let us adopt, but I'm so worried any human child would ask questions if I kept them in the dark! 'Daddy, why are you so strong? Why aren't you getting old? Why do you have a tail and fangs? Why're you on fire?' They'd get suspicious, and shy away…"

The boy looked up, finished with his canned meal. But rather than run away, he sat by Rin, smiling with the brown mixture all over his face and fingers. He made contented noises.

Rin rubbed the boy's hair as he continued speaking. "And if they knew I was a demon, if they knew I was the son of Satan, they'd think I was a monster and a freak, and be scared of me! My own kid!"

Yukio didn't answer for a moment, adjusting his glasses. It was subtle, but Rin could see his pained expression, these matters struck too close to home for him.

"…Your classmates weren't." He said quietly.

"Yes, they were. They needed time…even though they grew up believing in demons…The only one who didn't despise me at first was Izumo, and that was 'cause she's not entirely human herself…"

"Because it was right after you went out of control…" Yukio argued, as if trying to convince himself as well.

"There's that too. If that ever happened I could really hurt them. But I just don't want to adopt some normal kid and drag them into my life. I'd also watch them grow old and die…watching Izumo get gray hairs is already bad enough!"

Rin hugged the boy.

"Everyone around us is going to die soon! They'll get wrinkled and old and fall apart and then they'll die! You have...no idea.. how happy I am that you and Kuro are still gonna be around...But I want more than that! I just want a son who'll still be with us several centuries from now. He's my clone…he was made from me, so that makes him my son. This is my son."

"Nii-san…the reason he is not misbehaving right now is because I gave him a food formula reserved for positive reinforcement and rewards. He is momentarily pleased with the _food._ It's not because he likes you. He can't speak, he is at the mercy of his flames, and he has been raised like this for his entire life." Yukio sat down. "How are you going to convince him not to attack others? How are you going to teach him to communicate? To read and write? To wear clothes? To control his emotions? To reign in his power?"

"Somehow? Anyway, he was calm before you came back. He mellows out if he realizes he can't win a fight."

Yukio sighed.

"I don't feel like arguing with you. I'll talk to the new Paladin and the Grigori about this. There is a fair chance they'll let him live, but only if we prove he can be educated and tamed. They see the two of us as a boon rather than a bane, after all, maybe they will settle for a third one of us." Yukio explained as he pinched his nose.

"Yeah…" Rin agreed. Even if the Grigori were unwilling, the Paladin, Ryuuji Suguro, would advocate for them. He was their best friend of over twenty five years, he'd listen to them.

If the boy -who Rin decided to name Ryota after Suguro's son- continued to act wild, or if he didn't learn to control his flames, Rin knew he would have no choice but to kill him. And it would tear him apart. Until then, they'd have to keep him and raise him here, away from the rest of society until he was ready.


End file.
